A very large number of chair structures are known in the art, which are adjustable to permit the body of the user to assume a variety of positions, such as a reclining position for rest, a sitting position for writing at a desk and so forth. Many of said structures comprise a number of articulated parts, which swing relative to one another as the chair is adjusted from one position to another. Some of those chairs comprise a base, often in the form of a pedestal having a central column and a plurality of legs, to which the main structure of the chair is connected, by means of pivots, universal joints or the like. In some cases elastic elements are provided in the structure, whereby the chair may oscillate about a mean position, for the user's greater comfort. The last mentioned structures, however, generally do not permit the user to assume a reclining position and are capable of only limited angular displacement. In any case, structures that are widely adjustable and satisfactory from the viewpoint of the positions which they may assume, are complicated and relatively expensive to build.
It is a purpose of this invention to provide a chair which can be adjusted to assume practically any position that the user may desire, and yet is extremely simple in structure and economical to build.
It is another purpose of this invention to provide such a chair in which the user can assume either a substantially completely reclining position, or a sitting rest position, or a position adapted for writing at a desk.
It is a further purpose of the invention to provide such a chair, the structure of which comprises a minimal number of joints and particularly of pivots.
It is a still further purpose of the invention to provide such a chair which has a plurality of equilibrium positions coordinated to the position of the body of the user.
It is a still further purpose of the invention to provide such a chair which provides maximum comfort with the utmost structural simplicity.
Other purposes of the invention will become apparent as the description proceeds.